Perforator for water and oil wells

ABSTRACT

A device for perforating well casings so to increase a water or oil supply from the rock strata formation into the well, the device comprising an elongated billet lowered into the well, the billet including a plurality of pads around its outer side for positioning against the inner wall of the well, each pad having sharp curving edges, each pad containing explosives which is electrically ignited from above ground so that upon explosion the sharp edges of the pads crack the well casing.

United States Patent [72] Inventor Woodrow W. Johnson Box 348, Cle Elum, Wash. 98922 [21] Appl. No. 53,118

[22] Filed July 8, 1970 [45] Patented Dec. 14, 1971 [54] PERFORATOR FOR WATER AND 01L WELLS 4 Claims, 3 Drawing Figs.

[52] US. Cl 175/453, 175/456, 175/46 [51] lnt.Cl ..E2lb 43/117 [50] Field of Search 166/55, 55.1, 297, 207; 175/452, 4.53, 4.56, 4.6

[56] References Cited UNITED STATES PATENTS 1,380,182 5/1921 Bigelow 166/207 2,583,316 1/1952 Bannister. 166/207 X 2,587,244 2/1952 Sweetman 175/46 [I III /5 '1 g 1 II, IT ,1! in II II I1 if" 2,616,370 11/1952 Foster 175/4.6 X 2,686,472 8/1954 Burns l75/4.6 2,690,123 9/1954 Kanady 175/462 2,737,115 3/1956 Bissell l75/4.52 2,758,543 8/1956 Grandin 175/4.6 2,760,435 8/1956 Jones 175/4.52 3,415,321 12/1968 Venghiaths l75/4.6 X

Primary ExaminerDavid H. Brown Atmrney- Ford E. Smith ABSTRACT: A device for perforating well casings so to increase a water or oil supply from the rock strata formation into the well, the device comprising an elongated billet lowered into the well, the billet including a plurality of pads around its outer side for positioning against the inner wall of the well, each pad having'sharp curvizng edges, each pad containing explosives which is electrically ignited from above ground so that upon explosion the sharp edges of the pads crack the well casing. Y r

SPECIFICATION This invention relates generally to well construction equipment.

It is generally well known to those skilled in the art that a well in the ground for water or oil need not necessarily depend only upon a supply obtained from the lower end of the well pipe or casing but may be provided with an increase of supply from the rock strata formation on the side of the well casing. Accordingly it is desired that such well casing is perforated so to allow the supply to flow from the rock strata formation at the sides into the well.

Accordingly it is the principle object of the present invention to provide a device which offers a better way to perforate a well casing for obtaining such increased supply of oil or water.

Another object of the present invention is to provide a well casing perforator which incorporates a billet that can be lowered to the selected depth of the well and which incorporates explosive means for cracking open the well casing, the explosive means being controlled from above ground.

Other objects of the present invention are to provide a well casing perforator which is simple in design, inexpensive to manufacture, rugged in construction,easy to use and efficient in operation.

These and other objects will be readily evident upon a study of the following specification and the accompanying drawing wherein:

FIG. 1 is a perspective view of the present invention,

FIG. 2 is a detail view of one of the pads along the tube, shown enlarged, and

FIG. 3 is a cross-sectional view of a modified billet cylinder wherein additionally a vertically moveable wedge tightly fits the unit against the inner sidewall of a well casing pipe.

Referring now to the drawing in detail, and more particularly to FIGS. 1 and 2, the reference numeral represents a well casing perforator according to the present invention wherein there is an elongated, cylindrically contigurated billet 11 which includes a cylindrical sidewall 12.

The sidewall 12 is parted by a longitudinally extending slot 13 so that the cylindrical sidewall 12 can be diametrically expanded or contracted. The wall 12 is made of a plastic material of semirigid character so that the same is expandably flexible.

Upon the outer side of the sidewall 12, there is mounted a hollow tube 14 which is folded in longitudinal zigzag configuration so to form parallel rows 15 having semicircular turns 16 at their ends, the tube 14 thus forming a continuation completely around the entire outer side of the sidewall 12.

One end of the tube 14 extending upwardly is fitted with a plastic seal cap 17 into which there is affixed an electric dynamite cap 18. The cap 18 is secured to one end of an electric cord 19 the opposite end of which is connected to a manually controlled means for setting off an explosion.

The opposite end of the tube 14 also extends upwardly as shown at 20, and is open, as shown in FIG. 1 so to allow air to escape when the tube 14 is being filled at its opposite end with an explosive material.

Along the tube 14 there are affixed a plurality of pads 21, each pad being integrally affixed to the tube 14 and being positioned upon the radially outward side so that the pads can be positioned to face the inner wall of a well casing into which the billet is lowered. Each pad 21 comprises a hollow member, the interior of the pad communicating by means of a slot 22 with the interior of the tube 14 so that explosive material contained within tube 14 communicates with the interior of the pad.

A U-shaped handle 23 is secured to the upper end of the billet and provided with openings 24 and 25 therethrough.

The cylindrical wall 12 of the billet is maintained diametrically compressed by means of a plurality of hooks 26 secured fiivotally free upon pins 27, the opposite ends of the hooks 26 cok ng over outwardly extending pins 28, the hooks 26 thus abridging the slot 13 for drawing the opposite ends 29 and 30 of the sidewall 12 together.

A lug 31 on each hook is provided with an opening 32 to which there is connected a continuous cord 33 that extends upwardly through openings 24 and 25 of handle 23 and continues to extend upwardly out of the well where it may be manually controlled.

In operative use, the tube 14 is filled with an explosive in liquid form known as astrolite. It is exceptionally safe yet extremely powerful capable of exacting 8,600 pounds per square inch which is ample to penetrate a %-inch-thick well casing.

The billet 11 is then lowered into a well by a rope secured around the handle 23 until the billet is at a desired depth. At this depth, the cord 33 is pulled so to unhook the hooks 26 thus allowing the sidewall 12 to expand outwardly until the pads 21 rest against the inner side of the well casing.

It is to be noted that each pad is. provided with a pair of sharp edges 34 of chisel shape for transmitting breaking force against the well casing.

As shown in FIG. 1 of the drawing, it is to be noted that the pads are staggered along adjacent rows 15 and may be spaced apart 1 inch so to perforate a maximum pattern.

An electric charge now through electric cord 19 ignites the explosive, thus causing the pads directing force against the well casing which now crack the same. Thus an increasedflow of water or of oil is obtained.

The overall length of the billet may be approximately 3 feet, and if a longer pattern of casing shattering is required, additional billets can be attached piggyback thereto.

In FIG. 3 there is shown a modified billet 35 wherein the cylindrical sidewall 36 has a centnal opening 37 which is downwardly, inwardly tapered so that a weight 38 secured to a depending rope 39 can be forcibly dropped to a lower portion thereof, thus causing the sidewall 36 to expand, it being assumed that the sidewall also includes the vertical slot 13.

Thus a modified form for expansion of the sidewall is provided.

Thus there is provided a perforator which eliminates cumbersome expensive methods heretofore used and which ex pedites the entire operation. It eliminates possible loss of the entire well and equipment due to hangups of old methods.

What I new claim is:

1. In a well casing perforator, the combination of a cylindrical billet comprised of a cylindrical sidewall made of flexible plastic, said sidewall having a longitudinal slot across the entire length thereof so to form ends to permit said cylindrical sidewall to contract or expand, and exploding means around the outer side of said cylindrical sidewall.

2. The combination as set forth in claim I, wherein said explosive means comprises a zigzag tuhe secured to the outer side of said sidewall, said tube having a plurality of pads integral therewith and positioned to face outwardly each said pad having a plurality of longitudinally extending chisel edges on the outer side thereof, said each pad being hollow and communicating by a slot with an interior of said tube.

3. The combination as set forth in claim 2, wherein the ends of said tube extend upwardly, one said end being open, the other said end having a plastic seal cap secured thereto, said plastic seal cap having an electric dynamite cap secured thereto which is connected to one end of an electric cord for communicating with a manually controlled ignition means, said tube receiving a liquid explosive known as astrolite.

4. The combination as set forth in claim 3, wherein a plurality of hooks bridge said longitudinal slot between the opposite ends of said sidewall, said hooks being pivotable at their one ends about a pin, the opposite ends of said hooks being securable each over a hook on the outer side of said billet sidewall, each said hook being secured to a cord extending upwardly through openings formed in a U-shaped handle at the upper end of said billet for manual release of'said hooks.

l t l 4' 101014 MAI 

1. In a well casing perforator, the combination of a cylindrical billet comprised of a cylindrical sidewall made of flexible plastic, said sidewall having a longitudinal slot across the entire length thereof so to form ends to permit said cylindrical sidewall to contract or expand, and exploding means around the outer side of said cylindrical sidewall.
 2. The combination as set forth in claim 1, wherein said explosive means comprises a zigzag tube secured to the outer side of said sidewall, said tube haviNg a plurality of pads integral therewith and positioned to face outwardly each said pad having a plurality of longitudinally extending chisel edges on the outer side thereof, said each pad being hollow and communicating by a slot with an interior of said tube.
 3. The combination as set forth in claim 2, wherein the ends of said tube extend upwardly, one said end being open, the other said end having a plastic seal cap secured thereto, said plastic seal cap having an electric dynamite cap secured thereto which is connected to one end of an electric cord for communicating with a manually controlled ignition means, said tube receiving a liquid explosive known as astrolite.
 4. The combination as set forth in claim 3, wherein a plurality of hooks bridge said longitudinal slot between the opposite ends of said sidewall, said hooks being pivotable at their one ends about a pin, the opposite ends of said hooks being securable each over a hook on the outer side of said billet sidewall, each said hook being secured to a cord extending upwardly through openings formed in a U-shaped handle at the upper end of said billet for manual release of said hooks. 